should be a screw opposite side of switch from memory.Or once cover is off it is a "push fit".
geordie jim
November 2009
hi put a small screw driver down the side of the knob on the on off switch close to the body gently pull the knob up [make sure its unplugged ] when you have this out you will see a small screw take that out lift the rest is easy ,be very care full taking the knob they are easy to break the lug off the side
good luck
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